As the output of light emitting diodes (LEDs) has risen in recent years, it has become advantageous to use a package in which the main material of the support substrate is a ceramic with excellent resistance to heat and light (see, for example, WO2006/046655).
In the conductive wiring of such a package, conductive wiring of a surface including the part where a light emitting element is mounted is usually connected to conductive wiring applied to the substrate on which the package is mounted, so it consists of conductive wires on the rear face of the package and an inner-layer wire that links the conductive wires on the rear face with conductive wiring on the front face.
In general, the material of these wires is black or a color that is close to black, so the wires may absorb light from the light emitting element. In view of this, the wiring exposed from the package is electroplated with gold, silver, or another such metal to suppress the absorption of light, while the inner-layer wire that is embedded in the package is not electroplated and remains black. Also, since ceramic is a material that is generally porous and translucent, some of the light emitted from the light emitting diode may be transmitted through the ceramic and absorbed by the inner-layer wire embedded in the ceramic. As a result, a problem was that this lowered the light extraction efficiency of a light emitting device.